Nelson made the official announcement Monday morning at a campaign rally held at Textile Care Services in Rochester.

The three-year senator cut the rally short due to the mass shooting in Las Vegas. "We need to think of the victims, the families, those who are healing, many injured in last night's violence," she said during her less than 10-minute speech.

Rep. Nels Pierson (R - Rochester) introduced Nelson as "his senator" while welcoming her onstage. Nelson thanked supporters for being there, but she said this was not a day for campaigning. She then invited her church pastor, John Steer of Autumn Ridge Church in Rochester, to say a prayer for the victims and families impacted by the deadly mass shooting.

The nearly 100 people in attendance bowed their heads in prayer, thinking of the lives lost less than 12 hours earlier. As of Monday at noon, at least 58 people were killed and more than 500 injured in the shooting at a country musical festival in Las Vegas.

When the prayer concluded, Nelson spoke briefly before telling supporters she would see them in the coming days to have a "rah rah rally at a more appropriate" time.

Nelson said she has many days to talk about her vision for Congress. Before exiting the stage, Nelson told the crowd she looked forward to seeing them on the campaign trail. "May God bless America, may God bless Minnesota. Thank you so much."

The senator is seeking to replace current U.S. Rep. Tim Walz for Minnesota's first Congressional district. Walz is leaving Congress to run for Minnesota governor. Walz narrowly beat Republican Jim Hagedorn in November 2016, winning the seat by less than 1% of the vote.

Nelson is the second Republican to enter the race. Jim Hagedorn of Blue Earth is also in the running.